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T Electric Vehicle Potential in Australia Its Impact on Smart Grids
Electric Vehicle
Potential in Australia
Its Impact on Smart Grids
TAHA SELIM USTUN, CAGIL OZANSOY,
and ALADIN ZAYEGH
Image licensed by
Ingram Publishing
T
he availability of the technology and the promising acceptance of
hybrid electric vehicles (HEVs) has encouraged car manufacturing
companies to take solid steps toward the electric vehicle (EV) market.
As it is spread over a vast surface area, Australia has high car usage and
ownership rates, and the inefficiency of the public transportation system contributes to this.
Therefore, Australia has a very large potential market for EVs. In addition to the well-known
advantages, such as zero direct emissions, reduced dependency on oil, cheaper fuel, and more
silent operation through smart grids, EVs also offer a unique benefit called vehicle-to-grid (V2G) technology.
Through V2G technology, EVs can support better operation of the smart grids in terms of reliability and storage.
Based on reliable statistics and social studies, this article studies the EV potential of Australia and envisages
the impact of large EV utilization therein. The statistics indicate that the growing population will demand more
cars, and acceptance of EVs could also benefit other areas, such as environmental conservation, finance, and
energy production. Accordingly, a microgrid system with V2G technology has been modeled and simulated in
three different conditions: islanded, IEEE-T14-bus system, and IEEE-34-bus system. The results are presented to
Digital Object Identifier 10.1109/MIE.2013.2273947
Date of publication: 12 December 2013
1932-4529/13/$31.00©2013IEEE
december 2013 ■ IEEE industrial electronics magazine 15
forecast the necessary changes in the
power networks for the large deployment of EVs.
The concern of global warming is
a major issue that has been widely
discussed for many years. Faced with
serious consequences, governments
worldwide are enforcing plans for reducing carbon emissions [1]. By 2020,
some network operators in the United
Kingdom are planning to reduce carbon emissions by 45% [2], while European Union (EU) countries are obliged
to cut their emissions by 20% [3]. Australia, the country with the highest
carbon emissions per capita in the
world, has just introduced a carbon
tax. Other initiatives such as Beyond
Zero Emissions have been introduced
to help Australia transition to a carbon-free economy [4].
Internal combustion engines (ICEs),
which have provided the traction for vehicles for the past century, can only give
a maximum efficiency of 30% [5]. Considering increasing oil prices, an alternative to fuel is necessary for sustainable
transportation. This is also desirable for
the security policy of many countries
since it decreases dependency on foreign oil [6], [7].
The above-mentioned factors have
dramatically increased interest in
EVs [8]. For instance, the U.S. government has committed to a goal of
1 million plug-in EVs in the next five
years and will provide US$2 billion in
stimulus for battery development in
HEVs. A private organization, Google,
invested $US10 million in EV research
[9]. Different car manufacturing companies have already manufactured
plug-in HEVs (PHEVs), EVs, and HEVs
[10]–[13]. Various EV technologies
make it possible to meet demands
under different circumstances. HEVs
and PHEVs can assist in the gradual
introduction of EVs as they will provide a fuel-efficient option until the
necessary infrastructure required for
the large-scale introduction of EVs is
built. All the technology required for
EVs is readily available, and current
research focuses only on improving
performance or efficiency [5].
The statistical research on vehicle
use indicates that most vehicles are
used for short distances. Furthermore,
the majority of the vehicle fleet is idle for
the most of the time [2]. This gives sufficient time to charge the batteries, even
at average charging speeds. The ongoing research on battery technology and
smart grids is aimed at achieving supercharge capabilities [14].
When coupled with smart grid technology, an EV can act as a load as well as
a distributed storage device [15]. Being
connected to the grid when not in use,
the battery of the EV can supply power
at peak load times and thus increase
the power reliability of the grid. This
technology is called V2G [16]. Considering the total number of vehicles in a
locality, distributed storage capacity
provided by V2G can have a very large
impact on the economical operation of
smart grids [17].
Batteries
ICE
Generator
Power Electronics
Interface
Fuel Tank
FIGURE 1 – An HEV with a series hybrid power train.
16 IEEE industrial electronics magazine ■ december 2013
Propulsion
Motor
Australia is a very large continent
country with high motor-vehicle use
[18]. Wide-spread communities with
insufficient public transport service require Australians to drive more. The car
ownership ratio is very high, and the
growing population indicates that the
number of vehicles will also increase. It
is evident from the above data that Australia has a promising market for EVs.
Various EV Technologies
There are various EV technologies
available in the market. Some manufacturers have begun to adopt HEVs
for their improved efficiency, while
PHEVs are bringing the industry ever
closer to pure EV implementation.
Other manufacturers, such as Tesla
Motors, have dedicated their efforts
to developing pure EVs, which do not
even have a tail pipe [10].
HEVs are classified as series, parallel, and series–parallel hybrid power
trains [19]. Figure 1 shows a diagram
of a typical series hybrid power train.
Fed by a fuel tank, the ICE charges
the batteries through the generator.
The traction is provided to the wheels
through a battery-propulsion motor
couple. In a series power train, the
ICE is mechanically decoupled from
the wheels. This gives the freedom to
relocate the ICE as desired. Despite
expensive manufacturing costs, series
power trains are easy to design, control, and implement [19], and they are
popular for larger vehicles [5].
Figure 2 shows the topology of a
parallel hybrid power train where
both the ICE and the electric motor are
mechanically coupled to the wheels.
The electric motor helps increase the
efficiency of the ICE and decrease its
carbon emissions. One drawback of
parallel power trains is the inability
to operate in all-electric mode at high
speeds [5].
Figure 3 shows a PHEV with series–
parallel hybrid power train. It possesses
the advantages of both the series and
parallel hybrid trains. Since it has more
components, an additional generator is
compared with a parallel power train
and an additional mechanical link is
compared with a series power train.
Hence, it is more expensive. Thanks to
advancements in control and manufacturing technologies, these costs are reduced
and series–parallel power trains are
adopted more frequently [19]. Figure 3
also depicts the fundamental difference
between HEVs and PHEVs. The battery
system in a PHEV has an external connection and can be recharged independently from the operation of the ICE.
The motivation behind hybridization is to increase the overall efficiency of engines and decrease emissions
per unit distance. The benefits of
­hybridization can be summarized as
follows [5]:
1) Higher efficiency is obtained since
electric propulsion machines are
more efficient and faster than other
systems.
2) The flexibility provided by the electric propulsion systems makes it
possible to operate the engine at a
higher efficiency.
3) Regenerative braking can be used
to charge the batteries during
braking.
The hybridization factor of the
vehicles may vary depending on the
classification of HEV. Microhybrids
have a hybridization factor of 5–10%,
whereas mild hybrids have a 10–25%
hybridization factor. Higher values
are found in energy hybrids [5]. When
the need for an ICE and liquid fuel is
completely eliminated, a pure EV is
obtained. Furthermore, because of
their external electrical c­onnection,
PHEVs as well as pure EVs allow for
V2G operating modes.
Battery charging seems to be a
challenge for manufacturers, customers, and other parties. EV charging
requires special charging stations,
supply devices, and connectors. In addition to several issues such as charging through third parties, the most
important concern is the time required
to charge the batteries. Depending
on the electric network parameters
and the availability of the special
charging equipment, charging time
varies between 18 h and 20–50 min.
Table 1 shows the different charging
options available for EVs [5].
Only level 1 may not require
an upgrade of the existing electrical networks, while the remaining
three charging sets definitely would
require a thorough electrical network improvement. Level 1 is called
opportunity charging since it uses
low-peak periods and costs less,
but it takes a lot of time. Level 2 can
be used for home use. Public usage
means charging EVs when parked in a
Batteries
wer Electronics
Power
Interface
Propulsion
Motor
Mechanical
Coupling
ICE
Fuel Tank
FIGURE 2 – An HEV with a parallel hybrid power train.
Batteries
Power
Electronics
Interface
Propulsion
Motor
Generator
Mechanical
Coupling
ICE
Fuel Tank
FIGURE 3 – A PHEV with a series–parallel hybrid power train.
TABLE 1 – TYPICAL SET OF EV CHARGING OPTIONS [5].
CHARGING SET
UTILITY SERVICE
USAGE
CHARGE POWER (kW)
Level 1
110 V, 15 A
Opportunity
1.4
Level 2a
220 V, 15 A
Home
3.3
Level 2b
220 V, 30 A
Home/public
6.6
Level 3
480 V, 167 A
Public/private
50 –70
december 2013 ■ IEEE industrial electronics magazine 17
TABLE 2 – BATTERY CHARACTERISTICS OF DIFFERENT EVs.
MANUFACTURER
MODEL
EV TYPE
ELECTRIC
RANGE (km)
BATTERY SIZE
(kWh)
Toyota
Prius
PHEV
8
4
PHEV
16
8
Volt
EREV
64
16
Buick
Chevrolet
Fisker
Karma
PHEV
80
22
Nissan
LEAF
EV
160
24
Toyota
RAV4 EV
EV
190
27
Cooper (BMW)
Mini E
EV
251
28
Tesla
Roadster
EV
354
53
public place such as railway stations
or public car parks. Level 3, known as
fast charging, can be used by private
charging stations. EV owners can use
these stations for charging in a similar
fashion to petrol stations. Yet, in addition to electric network upgrades,
­level 3 charging requires special charging equipment [16].
The battery characteristics of different EVs are given in Table 2 [10]–[13].
The corresponding charging curves for
different EVs using different charging options are plotted in Figure 4. As shown,
level 1 is not feasible for some pure EVs
with large battery sizes. Level 3 seems
to be practical for all types, although it
is expected to be the most expensive
option of all. It is shown that levels 2a
and 2b are quite sufficient for almost all
EVs and can be implemented in parking places for short to medium parking
times (such as car parks near schools,
universities, business hubs, etc.).
EV Potential of Australia
Australian cities have traditionally
been spread over a wide surface area.
Additionally, Australians have a strong
taste for stand-alone buildings. It
seems that even the growing population in the cities has not changed this
40
35
Charging Time (h)
30
Charging Time (L1)
Charging Time (L2a)
Charging Time (L2b)
Charging Time (L3)
25
20
15
10
5
0
Toyota
Buick Chevrolet Fisker Nissan Toyota
BMW Tesla
Cooper
Manufacturer
FIGURE 4 – Charging time of several vehicles for different charging options.
18 IEEE industrial electronics magazine ■ december 2013
view. Consequently, the population
with lower income is pushed to the
outer fringes of the cities [19]. Figure 5
shows the scale maps of Melbourne
and Paris. Although they are spread
over a similar area, the population of
Paris is two and one-half times more
than that of M
­ elbourne [20].
However, the public transportation
network is much poorer in Australian
cities. This inevitably increases the
number of people who drive to work/
school each day. Figure 6 shows the total number of metropolitan passengers
each year in Australia. As shown, despite the rapidly increasing population,
the passenger load met by rail and
bus services has not changed significantly. The bulk of the load is still met
by privately owned passenger cars.
This pattern is almost identical for all
­Australian cities [21].
The research conducted by the Australian Bureau of Statistics reflects that
the structure of large cities makes it very
difficult to extend public transport to
every suburb; the frequency of the services is inadequate, and there is a general resentment toward public transport
services for various reasons such as
high ticket cost and safety concerns [18].
Therefore, as shown in Figure 7, the use
of public transport has been very low
in Australia. Nine out of every ten passenger–kilometers are covered by cars
while only one passenger–kilometer is
covered by rail or bus services.
When compared with other countries, Australia has one of the lowest
rates of public transport use in the
world. Figure 8 presents the results of
an International Union of Public Transport study conducted on selected cities in different countries [23].
As shown, the rate of public transport
use in selected cities in Australia and New
Zealand (Sydney, Melbourne, Brisbane,
Perth, and Wellington) was relatively low
by world standards, with an average of
5% of all trips made using public transport. Cities in the United States, including Los Angeles and New York, recorded
similarly low rates (3% of all trips).
In contrast, rates of public transport use were relatively high in both
western European (WEU) cities such as
London and Paris (19% of all trips) and
Population:
Population:
10 Million
4 Million
Paris, France
Melbourne, Australia
FIGURE 5 – Scale maps of Melbourne and Paris [20] and their respective populations.
250
200
Other
Rail
Bus
Car
150
100
Base-Case
Projections
50
19
4
19 5
4
19 8
5
19 1
1954
5
19 7
6
19 0
1963
1966
6
19 9
1972
7
19 5
1978
1981
8
19 4
1987
9
19 0
1993
1996
9
20 9
2002
0
20 5
2008
1
20 1
2014
1
20 7
20
0
FIGURE 6 – Total metropolitan passenger transportation for Australia (billion passenger–kilometer) [21].
1.0
0.9
0.8
0.7
0.6
Base-Case
Projections
0.5
0.4
Car + Other
Rail
Bus
0.3
0.2
0.1
0.0
19
4
19 5
4
19 8
5
19 1
1954
5
19 7
6
19 0
1963
1966
6
19 9
1972
7
19 5
1978
1981
8
19 4
1987
9
19 0
1993
1996
9
20 9
2002
0
20 5
2008
1
20 1
2014
1
20 7
20
high-income Asian cities such as Tokyo
and Hong Kong (30% of all trips) [23].
Because of the previously mentioned reasons, driving is not a luxury
but a necessity for Australians [24].
Passenger vehicle ownership is very
high in ­Australia, where 85% of the population owns at least one car [25] and
60% of households have two or more
cars [26].
As shown in Figure 9, in 2011, the
majority of 16,368,383 registered vehicles (a 2% increase from 2010) in
Australia, 76% (12,474,044) were passenger vehicles. Figure 10 shows that
the major part (72%) of the total kilometers (2,666 billion km) traveled in
2010 was, again, covered by passenger
vehicles [27].
The information presented clearly
shows that Australia has an enormous
passenger vehicle fleet, and because of
the insufficiency of public transport,
the base-case projections tend to indicate that the fleet will grow in numbers. This provides an opportunity for
introducing EVs in the future. However,
some of the contemporary EVs suffer
from low ranges. It is vital to investigate the daily vehicle use patterns in
Australia. Table 3 shows the average kilometers traveled by different vehicle
types annually and their corresponding daily usage [28]. On the other hand,
Table 4 reveals the distribution of passenger car use in terms of different
regions such as capital cities, urban
areas, interstate use, etc. The figures
for capital cities and urban areas are
accommodating even for the EVs using
existing battery technology [28].
According to a national survey, the
average travel time to work or school is
39 min for Australian drivers. The average travel time home is 40 min, while
the total daily average time of passenger vehicles is only 69 min [25]. This
implies that, on average, a vehicle is
used for 4.79% of the day and is idle for
95.01% of the time. In conclusion, there
is a big opportunity for V2G implementation in Australian smart grids.
Based on the battery characteristics
given in the “Various EV Technologies”
section, the maximum distributed storage that can be achieved with d
­ ifferent
vehicle types is shown in Figure 11.
FIGURE 7 – Proportion of passenger–kilometers: capital cities−1945 to 2020 [22].
Even if it is assumed that only 5% of
the vehicles will be EVs (the battery
capacity of a Toyota RAV4 EV is taken
as basis), this result yields 16.8 GWh.
Considering the isolated communities
of Australia, which run on standardalone grids [29], [30], these additional
storage devices (i.e., EV batteries) will
contribute toward the reliability and
protection of the grid.
december 2013 ■ IEEE industrial electronics magazine 19
which are calculated for three different
scenarios [34]. In the reference case,
Motorized Public Modes
it is assumed that no action is taken
Motorized Private Modes
by the governments to stabilize the
80
Nonmotorized Modes
carbon dioxide stabilization, whereas
in the 550 and 450 scenarios, it is as60
sumed that a global agreement is made
around stabilization of greenhouse gas
40
concentrations at 550 and 450 ppm
CO2-e, respectively.
20
Comparing the estimated EV demand (i.e., 16.8 GWh) with the curves
0
given in Figure 12, it is apparent that
USA
Aust/NZ
Canada
WEU
HIA
the impact on the national grid is negligible. If a complete EV migration is
FIGURE 8 – International comparison for levels of public transport [23].
assumed to occur in Australia, based
on Toyota RAV4 EV battery characteristics, the power demand
Impact on Grids in Australia
of EVs will be around 337 GWh.
EVs can be used to decrease
Heavy Rigid
Trucks
This value does not exceed 0.1%
vehicle-bound carbon emissions
2%
Other
of the power demand in 2011
in a very effective manner. For
2%
and 2012, shown in Figure 12.
instance, an analysis shows that
Motorcycles
4%
The impact of EVs is an issue
EVs will be a major factor for reat
the distribution level since
ducing carbon emissions in the
Light
it
becomes comparable with
transport sector beyond 2020
Commercial
Vehicles
the parameters therein. Figure
[31]. Based on this analysis, the
16%
13 shows the power demand
United Kingdom has introduced
per capita in Australia. When
measures for the uptake of EVs,
it is compared with the potenincluding support for vehicle
Passenger
tial power demand of EVs, it is
purchase and public recharging
Vehicles
76%
concluded that EVs will have a
points [18]. While a similar study
considerable impact. As menis yet to be performed in Austrationed earlier, 85% of the Australia, governments such as the Viclian population owns a car and
torian government support EVs
60% of households have two or
by running trials [32] to better FIGURE 9 – Ratio of motor vehicle types in Australia (2011).
more cars. This implies that 85%
understand the opportunities and
of the population will have EV
barriers for EV transition [18].
power demand added on their
One major concern about
power demand curve. It is also
widespread EV acceptance is
Heavy Rigid
discussed in the literature that
the immediate impact on elecOther
Trucks
introducing two EVs to a districity networks. Considering
3%
4%
tribution system is equivalent
the cumulative generation caMotorcycles
to introducing one new house
pacity of the power systems
1%
to the neighborhood [35]. Foland the estimated EV burden,
lowing the previous data, if it is
it is concluded that at power
Light
Commercial
assumed that 60% of the housegeneration and transmission
Vehicles
holds have only two cars, a full
levels, no major issue is an19%
EV migration will be equivalent
ticipated in power systems
to a 30% rise in the number of
[33]. Following the assumption
Passenger
the houses in the neighborhood.
made in the “EV Potential of
Vehicles
This will have a significant imAustralia” section, if only 5% of
73%
pact on distribution systems,
the vehicles are EVs with a batand it must be taken into account
tery capacity similar to that of a
by distribution companies.
Toyota RAV4 EV, the calculated
The chart in Figure 14 shows
power demand is 16.8 GWh.
Figure 12 shows the power FIGURE 10 – Percentage of total kilometers traveled in Australia the distribution of electricity consumption percentages according
demand curves of Australia, (2010).
%
100
20 IEEE industrial electronics magazine ■ december 2013
to the data provided by the Australian Energy Market Operator [36]. The
consumption regime also varies with
the widespread use of EVs. Depending on the charging method and the
location of the charging station, it is
expected that the residential and commercial electricity consumption share
will increase.
The impact of EVs as a load is one aspect, and the potential distributed storage provided is another. The estimated
amount of storage was presented in
the “EV Potential of Australia” section.
However, it is important to analyze
and compare the daily load profiles
with the daily vehicle usage regime.
Figure 15 shows the summer load profile of Australia. The curve is plotted
based on the data provided by [37] for
Ergon Energy, a distribution company
operating in Queensland, for the date
20 February 2011.
TABLE 3 – AVERAGE KILOMETERS TRAVELED BY DIFFERENT MOTOR VEHICLES IN 2010.
MOTOR VEHICLE TYPE
ANNUAL USE (km)
DAILY USE (km)
Passenger vehicles
13,200
36.2
Light commercial vehicles
17,500
47.9
Motorcycles
3,700
10.1
Heavy rigid trucks
20,800
57.0
TABLE 4 – USE OF PASSENGER VEHICLES IN 2010 (km).
CAPITAL
CITY
OTHER
URBAN
AREAS
OTHER
AREAS
TOTAL
INTERSTATE
INTERSTATE
AUSTRALIA
Total (million km)
95,619
30,787
31,400
157,806
5,555
163,360
Average
10,800
7,700
9,000
13,500
6,100
13,900
Daily use
29.6
21.1
24.7
37.0
16.7
38.1
700
1,400
600
1,000
400
TWh
300
200
100
9
Mwh Per Person
600
Reference Case
550 Scenario
450 Scenario
4
3
2
1
95
85
20
75
20
65
20
20
55
20
45
20
35
20
25
15
20
20
05
0
FIGURE 12 – Power demand curves for Australia [34].
Agriculture
1%
Transport and Storage
1%
Manufacturing
9%
Mining
9%
Residential
28%
Aluminum
Smelting
11%
Metals
18%
Commercial
23%
20
05
20
15
20
25
20
35
20
45
20
55
20
65
20
75
20
85
20
95
0
200
20
m
sa
a)
n
To
(L
yo
E
ta
AF
(R
AV )
C
oo
4E
pe
r ( V)
Te
M
sl
in
a
iE
(R
)
oa
ds
te
r)
t)
ar
(K
is
sk
er
ol
Fi
he
vr
C
N
ick
et
(V
ol
s)
Bu
riu
(P
a
To
yo
t
FIGURE 11 – Potential distributed storage with EVs in Australia (GWh).
6
5
800
400
0
7
Reference Case
550 Scenario
450 Scenario
1,200
500
8
distribution company operating in
New South Wales, for the date 24
August 2011. The reason for selecting two different regions and two
Figure 16 shows the winter load
profile of Australia. The curve is
plotted based on the data provided by [37] for Energy Australia, a
FIGURE 13 – Power demand per capita in Australia [34].
FIGURE 14 – Electricity consumption in Australia by sector.
december 2013 ■ IEEE industrial electronics magazine 21
Power Demand of the Loads
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
ERGON Energy–20/02/2011
Hour of the Day
Energy Australia–24/08/2011
V2G Opportunities
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Power Demand of the Loads
FIGURE 15 – A sample summer load profile for Australia.
Hour of the Day
FIGURE 16 – A sample winter load profile for Australia.
9
Total Daily VKT (%)
8
7
6
5
Cars
Motorcycles
LCVs
Buses
Articulated Trucks
Rigid Trucks
4
3
2
1
0
a­ fternoon. Figure 17 shows that vehicle
traffic drastically drops after 6 p.m.,
while load profile peaks around that
time. EVs, which will mostly be parked
in the garages of their owners, can
­provide energy to the grid throughout
the evening and get recharged during
the night.
Likewise, during winter, EVs can
support the grid in the evening when
electricity is required for heating,
­illumination, etc. It is apparent from
­Figure 16 that winter peak hours are longer and more dominant than summer
peak hours. The support of EVs during
these hours would be very beneficial.
Similarly, EVs can be programmed to
recharge during the night.
0 1 2 3 4 5 6 7 8 9 10 1112 13 14 15 16 17 18 19 20 21 22 23 24
Hour of the Day
FIGURE 17 – Daily regime of vehicle traffic in Australia—vehicle kilometer traveled (VKT) [21].
different distribution companies is
to depict the validity of EV potential
throughout Australia.
On comparing the load profiles
given in Figures 15 and 16 with the
daily vehicle traffic regime in Australia, given in Figure 17, it is concluded
that vehicle use behavior offers solid
opportunities for using EV batteries
as distributed storage as well as power
sources at peak hours.
In the summer, for instance, following rush hour in the morning, most
of the vehicles are parked at parking
lots (such as business hubs or school/
university parking lots). When they
are coupled to the grid, they can support the grid until rush hour in the
22 IEEE industrial electronics magazine ■ december 2013
Various simulations have been performed to analyze the impact of the
expected EV migration on Australian
electrical networks. The Paladin Design Base 4.0 software package was
used to model the components as well
as the networks. Considering a typical neighborhood, 30 Chevrolet Volt
EVs using the level 2a charging option
were taken as the basis for the simulations. Figure 18 shows the microgrids
topology used for the simulations.
V2G and grid-to-vehicle (G2V) cases are examined by modeling EVs as
power sources in the prior case and
as loads in the latter. For the sake of
simplicity, the charging and discharging characteristics of the EV batteries are assumed to be regular. The
microgrid system is connected to the
IEEE T14-bus system and the IEEE 48
bus system, shown in Figures 19 and
20, respectively, to investigate the behavior of the microgrid during V2G
implementation.
The simulation results are summarized in Table 5. Various parameters are
tabulated under operation without any
EV connection and operations under
V2G (EV supplying power) and G2V (EV
charging) conditions.
As mentioned in the literature
[33], [35], [40], EV connection does
not have any major impact on either
of the bus systems used. This shows
that V2G technology does not constitute a significant problem at the
TABLE 5 – SIMULATION RESULTS FOR TEST CASES.
ISLANDED OPERATION
IEEE T14 BUS
IEEE 34 BUS
Control parameter
V2G
G2V
V2G
G2V
V2G
G2V
VBus1
479.52 V
479.328 V
479.6 V
496.3 V
479.6 V
479.7 V
VBus4
479.76 V
479.424 V
479.8 V
496.4 V
479.8 V
479.5 V
VBus5
479.81 V
479.664 V
479.8 V
496.5 V
479.8 V
479.8 V
IBus1-Bus2
1,836 A
1,836.9 A
1,835.4 A
1,777.3 A
1,835.4 A
1,835.2 A
IBus1-Bus3
−1,836.3 A
−1,837.2 A
−1,216.8 A
−1296 A
−1,209.8 A
−769.1
IGrid-Bus1
N/A
N/A
4.3 A
13.23 A
14.7 A
27.8 A
IEV
−481.3 A
120.4 A
−481.2 A
113.67 A
−481.2 A
120.3 A
IDG3
−2,579.5 A
−2,483 A
−1,821.4 A
−1,833.1 A
−1,805.6 A
−1,808.1 A
IDG1
−2,481.8 A
−3,731.7 A
−2,481 A
−2392 A
−2,481 A
−2,480.8 A
Bus 1
CB2
1,837.2 A
CB1
1,836.9 A
Bus 3
Bus 2
CB3
2,483 A
CB5
674.3 A
CB4
4,231.5 A
CB6
2,489.7 A
Bus 4
Load 1
CB7
1,346.2 A
Bus 5
CB8
1,713.2 A
DG1
(Wind)1
CB9
CB10
2,427.1 A 3,731.7 A
CB11
1,345.4 A
CB12
120.4 A
GEN
DG2
(Solar)
Load 3
Load 2
DG3
DG4
(Diesel) (Fuel Cell)
V2G_Connect
FIGURE 18 – A sample microgrid with EV deployments.
transmission level. However,
this does not hold for distribution networks. When the impact of the EVs on the sample
microgrid is analyzed, it is
clear that large-scale mitigation
to EV technology will require
some changes to distribution
networks as well as their management and protection. Once
this challenge is managed, Australian electrical networks can
enjoy the benefits of next-generation EVs.
Similar Impact Studies
Around the World
The amount of research that
is being performed on EV
13
12
14
G Generators
C Synchronous
Compensators
G
C
1
11
10
9
C
7 8
6
4
5
2
G
Microgrid Point of Connection
3
C
FIGURE 19 – The IEEE T14 bus system with a microgrid point of
­connection [38].
migration and its impact on the
grids shows that EVs are very
popular and the migration of
vehicle fleets toward EV is very
probable. Almost all developed
countries have undertaken research to investigate their EV
potential and the expected impact. In this section, some of
these research studies will be
highlighted. For this purpose,
three types of countries are selected. The first group consists
of EU-member states, which
have small surface areas and
can be classified as “developed
countries.” There are various
research works focusing on EU
countries. The impact of the
december 2013 ■ IEEE industrial electronics magazine 23
G1
T1
Microgrid Point of Connection
848
846
822
844
820
864
842
818
802 806 808 812 814
850
824 826 858
834
816
888
860
836 840
890
832
862
800
T2
810
838
852
G2
828
830 854
856
FIGURE 20 – The IEEE 34 bus system with the microgrid point of connection [39].
Electric Vehicles Consortium led by CE
Delft, The Netherlands, with ICF, United
States, and Ecologic, Germany, as partners, conducted research on EU states
including Germany, Austria, and France
[41]. Other research groups focused on
the EV impact on the grid in Italy [42],
Switzerland [43], and the United Kingdom [44]. The United States, a large
country similar to Australia, is the
leading player in EV research. The Oak
Ridge National Laboratory is conducting research on the potential impact of
EV deployment on electrical regions in
the United States [45]. The third case
focuses on a small developing country,
Macau, which has a specific type of
­vehicle as the dominant type [46].
Regardless of the differences in
research parameters and the countries they are performed in, the estimated impact of EVs in the short
term is almost identical. The rate of
acceptance of EVs is limited by technical aspects and market parameters.
Therefore, the number of EVs in the
near future and the electrical load
constituted by them do not pose any
difficulties for generation and transmission. The only difficulty arises
at the distribution level, and all research work states that this can be
solved by means of smart charging
and/or dual-tariff utilization.
Conclusions and
Recommendations
Carbon emission reductions, renewable
energy use, and the desire to eliminate
the dependency on imported oil are
some of the reasons why EVs are very
popular. The availability of the technologies required and the higher efficiency
of electric cars has created a genuine
interest for EVs in the car market, and
many manufacturers have already assembled their own EV models.
Australia is a vast country, and its cities are traditionally designed to spread
over a large surface area. Given the
poor status of the public transportation
system and the general resentment of
Australians toward it, using a privately
owned car to travel to work and school
is the norm. Therefore, the car ownership ratio is very high in Australia, and
the market is promising for EVs. Network
grid operators and power engineers in
Australia need to consider the impact of
EVs on networks for future plans.
Furthermore, the popularity of EVs
is apparent from the impact studies
undertaken all around the world. Developed countries are undertaking studies
to estimate the level of EV migration in
the future and its impact on the electrical networks. The research shows that
the additional power demand introduced by EVs causes problems only at
24 IEEE industrial electronics magazine ■ december 2013
the distribution level. This can be easily
evaded by avoiding fast-charging methods or by implementing smart charging
methods. In this fashion, there can be
a smooth transition period where EVs
can be used and additional infrastructure can be built for full-fledged EV
migration.
Biographies
Taha Selim Ustun ([email protected])
received his B.E. degree in electrical and
electronics engineering from the Middle East Technical University, Turkey,
in 2007 and his master of engineering
science degree from the University of
Malaya, Malaysia, in 2009. He received
his Ph.D degree in electrical engineering from Victoria University, Melbourne, Australia, in 2013. Currently,
he is an assistant professor in electrical
engineering, School of Electrical and
Computer Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania. His research interests are power
systems protection, communication in
power networks, distributed generation, microgrids, and smart grids.
Cagil Ozansoy received his B.Eng.
degree in electrical and electronic
engineering (hons.) from Victoria
University, Melbourne, Australia, in
2002. In 2006, he completed his Ph.D.
degree in the area of power system
communications. He is currently a
lecturer and researcher in the School
of Engineering and Science, Victoria
University. His major teaching and research focus is on electrical engineering, renewable energy technologies,
energy storage, and distributed generation. He has successfully carried out
and supervised many sustainabilityrelated studies in collaboration with
local governments in the past. He has
more than 25 publications detailing
his work and contributions to knowledge. He is a Member of the IEEE.
Aladin Zayegh received his B.E. degree in electrical engineering from Aleppo
University in 1970 and his Ph.D. degree
from Claude Bernard University, Lyon,
France, in 1979. He has held lecturing positions at several universities and, since
1991, he has been at Victoria University,
Melbourne, Australia. He has been the
head of the school and a research director, and he has conducted research,
supervised several Ph.D. students, and
published more than 250 papers in peerreviewed international conferences and
journals. He is currently an associate professor at the School of Engineering and
Science, Faculty of Health, Engineering,
and Science at Victoria University, Melbourne, Australia. His research interests
include renewable energy, embedded
systems, instrumentation, data acquisition and interfacing, and sensors and
microelectronics for biomedical applications. He is a Member of the IEEE.
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december 2013 ■ IEEE industrial electronics magazine 25
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